Mechanical backstop for pin setting machines



March 26, 19.68 F, OMS 3,375,00

' MECHANICAL BACKSTOP FOR PIN SETTING MACHINES- Filed Aug. 12, 1 965 7 5 sheets-sheet 1 /-vE/v ron' CL v05 F DA v/s March 26, 1968 CREW/.5 3,375,006

MECHANICAL BACKSTOP FOR PIN SETTING MACHINES Filed Aug. '12, I965 5 $heets-$heet z M v \\E ATTYSI March 26,

1,968 I F. DAVIS MECHANICAL BACKSTOP FOR PIN SETTING MACHINES Filed Aug. 12, 1965 Y 5 Sheets-Sheet 5 lNVENTOR CLYDE. F. 0/1 V/s I United States Patent ington I Filed Aug. 12, 19 65 Ser. No. 479,230 6 Claims. (Cl. 27349) This invention relates to a novel mechanical backstop or pit cushion for pin setting machines such as are used at the rear of bowling alleys.

Automatic pin and ball handling devices used in conjunction With bowling alleys rely upon speed of operation for efiicient use. The cost of the machine installations, as well as the expense of maintaining and operating such alleys, require that every possible effort be made to minimize lost time between each delivery of a ball by a bowler. Many different devices have been incorporated in such machines to speed up the return of balls, to speed up the setting of the pins, and to generally facilitate the utilization of the alleys at every possible moment. The present invention is concerned with the alleviation of one area ofdelay, namely the delay that occurs in conventional installations between the time that a ball strikes the backstop or pit cushion and the time in which it is received within the ball elevator. The ball elevator is the mechanism which lifts the ball to return it to the front of the alley.

It is a first object of this invention to provide a pit cushion assembly that will yield upon impact of a ball and which will slow the ball without causing it to rebound in a forward direction.

Another object of this invention is to provide such an assembly that can be readily incorporated in existing machines as a substitute for the conventional solid pit cushion.

Another object of this invention is to provide an assembly which will automatically lift the lower portion of the pit cushion upon impact by a bowling ball, the assembly being designed to mechanically lift the cushion to a height sufficient to provide clearance of the bowling ball during passage of the ball to the ball elevating conveyor.

These and further objects will be evident from the following disclosure, taken together with the accompanying drawings, which illustrates a preferred form of the invention.

In the drawings:

FIGURE 1 is a sectional elevation taken through the lower rear section of an automatic pin and ball handling apparatus equipped with the instant device;

FIGURE 2 is a fragmentary rear view of the apparatus seen in FIGURE 1 along line 22;

FIGURE 3 is an enlarged fragmentary sectional view taken along line 33 in FIGURE 2, showing the device in its raised condition; and

FIGURE 4 is a view similar to FIGURE 3, but taken along line 44 in FIGURE 2.

The device described below is a pit cushion assembly designed to be incorporated in a mechanical pin setting device such as the automatic pin and ball handling machinery manufactured by the Brunswick Corporation. The apparatus is adapted to be mounted in such machinery in place of the conventional one piece backstop or rear pit cushion that serves to stop the rearward movement of the ball after it has left the bowling alley and also trips the mechanism to initiate the setting of the pins.

As seen, this assembly is mounted on the fixed framework of the pin setting machine. In place of the conventional pit cushion or backstop, there is provided a pit 3,375,006 Patented Mar. 2 6, 1968 cushion having a relatively stationary section of sheet material 10 draped across upper and lower rods 11, 12 carried on a mounting bracket 13 at each side of the pit area and fastened to the upright pit side walls 14 by means of upper bolts 15. Sheet 10 is made of any suitable flexible or semi-flexible sheet material capable of withstanding the shock to which it will be subjected due to flying pins. At the bottom of sheet 10 is a padded lower portion of the pit cushion designated by the numeral 16. This portion 16 extends transversely across the full width of the pit cushion and protrudes both downwardly and rearwardly from the lower rod 12. It is pivotally mounted for movement about a transverse horizontal axis by sleeves 17 which receive pivot shafts mounted on the respective brackets 13.

When in its initial or lower position, with its lower edge beneath the elevation of the top of a bowling ball resting on the pit floor 18, the lower portion 16 of the pit cushion will be swung rearwardly about the axis of sleeves 13 by impact of a ball rolling rearwardly on the pit floor 19. To absorb this movement and positively control the pivoting movement of the lower portion 16 of the pit cushion, the mechanical apparatus shown in the drawings is connected to the lower portion 16 of the pit cushion. This apparatus comprises a mounting bracket 18 fixed to the rear cross bar 20 of the conventional machinery frame. The bracket 19 rotatably supports a cam member 21 by means of bearings 22, 23. The cam member 21 is provided with an outer surface configuration having a first area 21a with a smaller radius than a second area 2112. The angular dimension of the peripheral area 21b is preferably less than degrees. The periphery of cam member 21 is contacted by a switch control lever 22 of a switch 23 fixed to the bracket 18. The switch 23 is actuated at all times except when the lever 22 is depressed upwardly by contact with the area 21b of greater radius about the periphery of cam member 21. Thus, switch 23 will be actuated during a period of revolution of cam member 21 greater than 180 degrees. The cam member 21 is mounted on a shaft 24. It is selectively connected to shaft 24 through an electrically operated clutch 25 selectively engageable to cause rotation of the cam member 21 in unison with shaft 24. By the same token, clutch 25 is selectively disengageable to permit free rotation of cam member 21 about the axis of shaft 24.

Shaft 24 is continuously rotated by means of a chain 26 and sprocket 27 powered by an auxiliary sprocket 28 coupled to the conventional pulley 30 for the pin conveyor 29 above the pit area. The pulley 30 operates continuously during the operation of the machine and therefore rotates shaft 24 at a continuous rate of speed.

The cam member 21 is coupled to the lower portion 16 of the pit cushion by means of a rigid adjustable connecting link 31. Link 31 is pivotally connected at 32 to the rear surface of the lower portion 16 of the pit cushion. It is pivotally connected at 33 to the cam member 21. The location of the pivot connection 33 is such that the normal lowered position of the portion 16 of the pit cushion, due to its own weight, will be such as to place the contact portion of switch lever 22 adjacent to the angular end of the cam peripheral area 2111 on cam element 21 in its normal direction of rotation (arrow 34). Thus, any rearward motion of the lower portion 16 of the pit cushion will cause initial pivotal movement of the cam member 21 in the direction indicated by arrow 34'. This will initially release the switch lever 22 from contact with the peripheral cam configuration 21b, which will activate the switch 23.

Switch 23 is coupled to the control of clutch 25, and, when actuated, energizes clutch 25 to couple shaft 24 3 and cam member 21. This will result in continued rotation of the cam member 21 in the direction shown by arrow 34', the rate of speed of rotation of cam member 21 being governed by the relative sizes of the sprockets 27, 28, as well as the speed of pulley 30.

Once tripped, switch 23 will remain actuated until lever 22 again reaches the cam configuration 21b. This will occur after a period of rotation greater than 180 degrees. At this time, the clutch 25 will be disengaged to free the cam member 21.

Since it is desirable that the lower portion 16 of the pit cushion remain in an upper position until the ball and pin elevating mechanism have definitely cleared the pit table 19, the downward movement of the lower portion 16 of the pit cushion is restricted beyond release the cam member 21. This is accomplished by a solenoid controlled mechanical stop 34 mounted on bracket 18 and operated by a solenoid 35 (FIGURES 3, 4). Stop 34 is normally extended by action of a tension spring 36 fastened between stop 34 at its lower end and the upper portion of the sleeve 37 within which it slides. Stop 34 is selectively retracted by actuation of solenoid 35.

A pin 38 is shown fixed to the back side of cam member 21, the rotational path of pin 38 being such as to intersect the extended location of stop 34. The angular position of pin 38 is such that it will abut stop 34 immediately following release of clutch 25 by operation of switch 23. Thus, stop 34 results in the holding of the position of the lower portion 16 of the pit cushion as shown in FIGURE 3, following release of clutch 25.

Solenoid 35 is activated by a switch on the pin setting machine that is operated by movement of any suitable mechanical device at the time desired for release of cam element 21. In a typical installation, this switch (not shown) would be operated by the rake arm on the detector housing so that the switch is closed to complete the circuit to solenoid 35 at the time that the rake arm returns to its normal position at the end of a pin setting cycle. Momentary release of the solenoid 35 will permit the pin 38 to pass stop 34 as the lower portion 16 of the pin cushion pulls downwardly on the link 31 due to its own weight.

Thus it can be seen that each bowling ball 40 that contacts the lower portion 16 of the pit cushion will cause initial angular movement of the cam element 21 sufiicient to actuate switch 23 and lock cam element 21 to the constantly rotating shaft 24 by operation of clutch 25. The mechanical rotation of cam element 21 will then positively lift the lower portion 16 of the pit cushion to a ball passing position to permit rearward passage of the ball 40 to the ball elevating mechanism generally designated by the numeral 41. The ball will proceed rearwardly with little or no rebound and with a minimum amount of lost time. The pit cushion will present no possible obstacle to rearward passage of the ball. The portion 16 will remain in its elevated position (FIGURES 3, 4) after the energization of clutch 25, due to the action of stop 34. After the pin setting operation has proceeded to a point near completion, the controlling switch for solenoid 35 can be tripped, permitting the portion 16 to pivot downwardly to its initial position (FIGURES 1 and 2).

Many minor modifications could be made in this assembly without deviating from the basic structure as described, various changes must be made in order to adopt this particular device to different types of automatic pin and ball handling equipment, but the basic concept of an initially actuated moving pit cushion portion and a mechanical device to positively control the elevation of that portion following initial impact will be retained. For these reasons, the structure just described is set out only by way of example and is not intended to limit or restrict the scope of my invention.

Having thus described my invention, I claim:

1. A pit cushion assembly for an automatic pin and ball handling mechanism at the rear of a bowling alley, comprising:

a stationary framework;

a pit cushion on said framework extending transversely across the pit at the rear of a bowling alley, said cushion including a lower portion pivotally mounted on said framework about a horizontal transverse axis;

a member rotatably mounted on said framework about an axis parallel to said horizontal transverse axis; linkage means operatively connected to said member and said lower portion of said pit cushion to initiate rotation of said member upon rearward swinging motion of said lower portion;

and drive means operatively connected to said member to continue to rotate said member about its axis, said drive means being responsive to initial rotational movement thereof caused by pivotal motion of the lower portion of said pit cushion thereby raising said lower portion to a ball passing position.

2. An assembly as defined in claim 1 wherein said drive means comprises:

a constantly rotated motor;

a selectively engageable drive mechanism operatively connected to said motor and said member;

a control switch on said framework adapted to control engagement of said drive mechanism;

and a cam surface on said member in operative engagement with said control switch.

3. An assembly as defined in claim 1, further comprising:

releasable means on said framework selectively engageable with said member to limit the amount of rotation thereof following movement of said lower portion to a ball passing position.

4. A pit cushion assembly for an automatic pin and ball handling mechanism at the rear of a bowling alley, comprising:

a stationary framework;

a pit cushion on said framework extending transversely across the pit at the rear of a bowling alley, said pit cushion including a lower portion having an initial position relative to said framework protruding downwardly from a first horizontal transverse axis about which it is pivotally carried on said framework;

a member rotatably mounted on said framework about a second axis parallel to said first horizontal transverse axis;

a rigid link pivotally connected at one end to the lower portion of said pit cushion about an axis parallel to and radially spaced from said first axis, the remaining end of said link being pivotally connected to said member about an axis parallel to and radially spaced from said second axis, the position of said axes at the respective ends of said link being such that a plane containing both axes is radially displaced from said second axis when the lower portion of said pit cushion is in its initial position;

disengageable drive means for selectively rotating said member about said second axis;

and control means on said framework operatively engaging said member to successively connect said drive means to said member upon initial rotation of said member caused by rearward pivotal motion of the lower portion of said pit cushion and then to release such connection when said element has been rotated to an angular position about said second axis wherein the weight of said lower portion of said pit cushion acting through said link is capable of returning said member to its initial position. 5. An assembly as defined in claim 4 wherein said control means comprises:

switch means wired to said drive means to connect said drive means to said member;

and a cam surface formed on said member in engagement with a switch control lever of said switch means, said cam surface having a radial configuration such that said switch will be activated, following initial angular motion of said member about said second axis, during continued angular movement of said member of a magnitude greater than 180 degrees.

6. An assembly as defined in claim 4 wherein said control means comprises:

a switch means wired to said drive means adapted, when activated by positioning of a switch control lever, to connect said drive means to said member;

and a cam surface formed on said member in engagement with the switch control lever of said switch means, said cam surface having a radial configuration such that said switch will be activated, following initial angular motion of said member about said second axis, during continued angular movement of said member of a magnitude greater than 180 degrees;

and releasable stop means on said framework and said member operatively engageable to prevent further rotation of said member about said second axis following release of said switch means.

References Cited UNITED STATES PATENTS 3,233,901 2/1966 Sandahl 273-53 3,248,110 4/1966 Weeb 273-53 X 3,319,959 5/1967 Lenhart 273-53 X ANTON O. OECHSLE, Primary Examiner.

M. R. PAGE, Assistant Examiner. 

1. A PIT CUSHION ASSEMBLY FOR AN AUTOMATIC PIN AND BALL HANDLING MECHANISM AT THE REAR OF A BOWLING ALLEY, COMPRISING: A STATIONARY FRAMEWORK; A PIT CUSHION ON SAID FRAMEWORK EXTENDING TRANSVERSELY ACROSS THE PIT AT THE REAR OF A BOWLING ALLEY, SAID CUSHION INCLUDING A LOWER PORTION PIVOTALLY MOUNTED ON SAID FRAMEWORK ABOUT A HORIZONTAL TRANSVERSE AXIS; A MEMBER ROTATABLY MOUNTED ON SAID FRAMEWORK ABOUT AN AXIS PARALLEL TO SAID HORIZONTAL TRANSVERSE AXIS; LINKAGE MEANS OPERATIVELY CONNECTED TO SAID MEMBER AND SAID LOWER PORTION OF SAID PIT CUSHION TO INITIATE ROTATION OF SAID MEMBER UPON REARWARD SWINGING MOTION OF SAID LOWER PORTION; AND DRIVE MEANS OPERATIVELY CONNECTED TO SAID MEMBER TO CONTINUE TO ROTATE SAID MEMBER ABOUT ITS AXIS, SAID DRIVE MEANS BEING RESPONSIVE TO INITIAL ROTATIONAL MOVEMENT THEREOF CAUSED BY PIVOTAL MOTION OF THE LOWER PORTION OF SAID PIT CUSHION THEREBY RAISING SAID LOWER PORTION TO A BALL PASSING POSITION. 